STELLAR CORONAL ABUNDANCES .3. THE SOLAR FIRST IONIZATION-POTENTIAL EFFECT DETERMINED FROM FULL-DISK OBSERVATION

In this paper we reanalyze the full-disk quiet-sun spectrum of Malinov sky and Heroux (1973) with modern atomic data. The purposes of this ar e to check our atomic data and methods in other investigations using d ata from nearby stars obtained with the NASA Extreme Ultraviolet Explo rer satellite, and to confirm that the solar FIP effect investigated b y previous authors studying discrete solar regions is the same as that found in full-disk spectra. We recover the usual solar FIP effect of a coronal abundance enhancement of elements with a low first ionizatio n potential (FIP) of a factor similar to 3-4 for lines formed at tempe ratures greater than similar to 10(6) K. For lower temperatures, the F IP effect seems to be substantially smaller, in qualitative agreement with other data. Comparing our fill-disk result with those from discre te solar structures suggest that the FIP effect is a function of altit ude, with the lower temperature full-disk emission being dominated by the super-granulation network. We also compare the recent Fe ionizatio n balance of Arnaud and Raymond (1992) with that of Arnaud and Rothenf lug (1985).